Photographic shutter



Jan. 9, 1940. M. R. HUTCHISON, JR 2,186,639

PHOTOGRAPHIC SHUTTER Filed March 14, 1939 I MALE/2 RfiurcH/w/vJ/z IN VENT OR WW BY M76 A TTOR NE YS Patented Jan. 9, 1940 UN-lrT ED STATES PATENT OFFICE PHQTOGRAPHIC SHUTTER Application Mm'ch il 1, 1939, Semi No, 2131,7112

9 (Claims.

This invention relates to photography, and more particularly to a simple type of shutter for photegi'ephic cameras.

Cue object of my invention is to provide at shutter which has a positive means for making 2, light-tight closure completely around the apes ture through which an exposure mey be made. Another object of invention is to provide a shut-tel with. a means of preventing rebound, which means also assist in forming a lielit tteizt connection with the shutter supportlzig plate. St another-r object of my ii'zventlon is to provide and inexpensive type of shutter which lfGUullleS a, mi onum degree of slzill in assembling claims 5?;

231} accords, ce

; t mes of shutters, lo. wine a. c-ci perforat d piece so -v shutter me;

ion ant er; expose. the shutter, is frequei ol 'o perfectly ii i 3 across e2: the eperturecl (Cl. SIB-6M porting plate, and also prevent rebound oi the shutter blade upon completion of an exposure. Referring to l, the camere body 5 may include the usual from; penel '2, listing at lens fl mounted in a lens cell 3 and includ ng s, time lever provided e handle on the frost wall of the camera. The top wall lslclude a view and e trigger of the type which be olepsessed for making an exeosw'e. Referring to 2, the shutter is pa'etez'sbly essemolecl on e shutter plate 23 one; the trlgge may lee eel-nee the plate e upon 2: pair of studs ill passing through slots 5 l in a slide mom l2 the trigger. l. e s comics e. spring; em! vl'iiclo is adopted engage either one of two similar? notches on the lever which is mountecl to esteel anal which e l"? lying in not-22o stai 'c' zlclz supports. opposite 1 Toy es eradicat comelete A "use sees-lure to seceive e complementary by the shutter plate 1g ca: shutter plate carries two of these eer- $22, liossie s, Fig. only one of villi to coopeie-te with t e emoossing mound aperture when shutter is at other tending to tilt the slew er islet e st angle shutter plate as in 3. Thus, when the trigger is cleesessed end. the lever is mover} to ten" sion the spring to, as soon as a tension is built up siotirsg by the stud. passing the stud 1' I 2|, the spring will urge the shutter plate in the direction shown by the arrow in Fig. 2. Since the spring is sufflciently heavy to cause the embossing 3| to slide up over the walls of the embossing 30, the shutter plate will rapidly move until the rounded edge of the plate strikes the stop pin 33, at which point the opposite embossing 3| will have reached the embossing 30 and will slide down into this embossing. Since the two embossings are sufficiently deep to hold the shutter blade in its position of rest, there is no possibility of the plate rebounding or vibrating to such an extent that light; will be permitted to enter the aperture 25. Moreover, as indicated in Fig. 3, the two embossings form a light lock completely surrounding the aperture so that in spite of the fact that the plate 22 hascomparatively little overlap with the exposure aperture 25, a perfectly light-tight joint is provided.

Since the shutter plate 22 is normally made fiat, except for the embossings 3|, one of these embossings always rides on:the surface of the plate 9 and tends to press the opposite embossing immediately into the embossing when the shutter reaches its position of rest.

With the construction just described, it will be seen that by merely adding cooperating embossings to the shutter supporting plate and to the shutter blade itself, I have provided a structure which accomplishes a number of functions without the use of added parts. First, the complementary-shaped embossings provide a perfectly light-tight joint between the shutter blade and the shutter supporting plate when the shutter blade is in its position of rest. Second, the interengaging embossings tend to hold the shutter blade against movement until sufiicient energy has been stored up in the spring 20 to swing the shutter blade in such a manner that one embossing leaves the other so that the shutter blade will continue to swing and light may pass through the aperture 24 until the shutter blade reaches its position of rest with the opposite embossing engaged in the shutter plate embossing. Third, as the shutter blade approaches its position of rest, one of the embossings on the shutter blade rides on the surface of the shutter plate so that as soon as the embossing 30 is reached by the opposite embossing on the shutter blade, it immediately drops down into the embossing, as indicated in Fig. 3. This is accomplished without any spring in the shutter blade itself, and is due entirely to the formation of the embossings on the shutter blade.

While it is obvious that the shape of the embossings and the position of them may be somewhat altered, I have illustrated a preferred form of embossing which can be readily formed in the metal of which the parts are made, and which are so shaped that there is little likelihood of breaking the metal during the forming operations. At the same time, the two formings are substantially complemental in shape so that it would be quite impossible for light to pass through the aperture 25 and around the embossings in such a way as to fog the film.

The embodiment I have just described illustrates a shutter of the type in which the blade moves in one direction to make one exposure and in a reverse direction to make a second exposure. Obviously, the interfitting embossings or formings are equally useful in other types of shutters, and accordingly, in Figs. 4 and 5, I have illustrated a shutter of the blade and cover blind ailsaeso type as a second embodiment of my invention and as illustrating a shutter of the type in which the shutter blade always moves in one direction to make an exposure and then moves in a. reverse direction in returning to its initial position of rest.

In this type of shutter it is only necessary for the shutter blade to beprovided with a single embossing, since the single embossing will always lie opposite the exposure opening.

In Fig. 4, there is a shutter supporting plate 50, carrying a stud 5| which movably supports the shutter blade 52. This shutter blade is provided with the usual exposure slot 53 which is so positioned relative to the stud 5| that when the shutter blade moves, it is swung past an exposure opening 54 in the plate through which light rays pass to make a picture. This shutter blade is attached at 55 to one end of a hairpin spring 55, the other end of which 51 is attached to an arm 58 carried by the cover blind 59, pivoted at 60, and also carrying the trigger handle 6|. A spring 62 normally holds the cover blind in the position shown in Fig. 4. In this position, the shutter blade is in its normal position of rest with the lug 63 resting against a stop 64 and with an annular embossing 55, best shown in Fig. 5, lying in engagement with a substantially embossing 56 encircling the exposure aperture 54. In this position, of course, it is not possible for light to enter the aperture 54 and pass around the edges of the shutter blade 52.

When the trigger BI is depressed, the cover blind 59 will move from over the top of the exposure aperture 54 and as soon as the stud 51 moves a distance suflicient to tension the hairpin spring 56 and to pass a dead center with respectto the stud 5|, the shutter blade 52 moves so that the aperture 53 crosses the exposure aperture 54, making an exposure.

As in the first described embodiment, the complementary embossings 65 and 66 perform the additional useful function of tending to retain the shutter blade 52 against movement until sufficient power has been stored in the spring 55, at which time the embossing on the shutter blade slips out of the embossing on the supporting plate as the shutter swings to make an exposure. The embossing 65 will slide over the plane surface of the supporting plate 50, and after the trigger BI is released and the cover blind covers the aperture 54, the spring 56 will again be tensioned and released so that the shutter blade may turn in the reverse direction about its pivot until the embossing 65 reaches and drops into the embossing 65 on the supporting plate. As soon as this position is reached, there is a triple light-tight joint, that is, the embossings 65 and 66 form one tight connection and the cover blind 59, which is somewhat larger in size, overlies both the shutter blade and the exposure opening. It should be noticed that when the shutter blade is swinging to its initial position of rest after an exposure has been made, the walls of the complementary-shaped embossings 65 and 66, being bent from the plane of the metal plates from which they are made, provide a braking action which beings the shutter blade smoothly to rest and at the same time prevents rebound. With this type of shutter, I have not found it necessary to provide an embossing or protuberance opposite to the embossing 65 to tilt the shutter blade as in the first embodiment of my invention, since it works entirely satisfactorily complementary-shaped annular amass:

without any such arrangement. However, it

would be quite possible to add on a second embossing similar to the first, but spaced on an opposite side of the pivot I, it it should be deemed 3 necessary.

I have described two preferred embodiments of my invention but obviously other types of shutters could be equipped with the complementeary-shaped areas formed to one side of the plane of the metal of which they are made so as to form rebound checks, light-tight connections and a means for holding back the shutter blade until the spring is properly tensioned.

What I claim as my invention and desire to be secured by Letters Patent of the United States is: I

in a photographic shutter, the combination with a supporting plate having an exposure aperture therein, a forming around the aperture, a ivotally mounted shutter blade, means for movie the shutter blade relative to the aperture to make an exposure, a forming carried by the shutter blade substantially complemental in shape with the forming around the aperture and adapted to rest therein when the shutter blade is in a position of rest.

In a photographic shutter, the combination with a supporting plate having an exposure aperture therein, an annular recess extending around the exposure aperture, a movable mount-=- ed shutter blade adapted to move relative to the aperture to permit light to pass therethrough and to a position of rest, an annular forming carried by the shutter blade adapted, when the blade is in its position of rest, to form a light-tight con nection-udth the annular forming on the supporting plate.

3. a photographic shutter, the combination with supporting plate having an exposure I aperture therein, a forming around the sper ture, a pivotally mounted shutter blade including an aperture, and similar i'ormings on the shut ter blade at each end oi: the aperture, the position oi each forming being such that one forming may rest in and form light-tight connection with the forming about the shutter support aperture, a shutter trigger, and means actuated by the trigger and including a spring for swinging the shutter about its pivot to make an exposure, one forming leaving the supporting plate forming as the shutter aperture passes through its path to make an exposure, the other forming coming to rest in the shutter plate forming as the exposure is completed.

4.. In a photographic shutter, the combination with a supporting plateincluding an exposure opening, a shutter blade movably mounted on the plate, means for moving the blade to uncover and cover the aperture to make an exposure including a trigger, and a spring adapted to be tensioned and released by the trigger, cooperating embossings on the shutter blade and support normally forming a light-tight connection when theshutter blade is in a position of rest, said supporting plate embossing completely encircling the exposure opening.

5. In a photographic shutter, the combination with a supporting plate including an exposure opening, a shutter blade movably mounted on the plate, means for moving the blade to uncover and cover the aperture to make an exposure including a trigger, and a spring adapted to be tensioned and released by the trigger, cooperatin: em on the shutter blade and support normally forming a light-tight connection when the shutter blade is in a position or rest, said supporting plate embossing completely encircling the exposure opening, said embossings including interfitting curved walls so shaped that at least parts of, the walls extend into telescopic relationship when said shutter is at rest. v

6. in a photographic shutter, the combination with a supporting plate including an exposure opening, a shutter blade movably mounted on the plate, means for moving the blade to uncover and cover the aperture to make an exposure, including a trigger, and a spring adapted to be tensioned and released by the trigger, co-

operating embossings on the shutter blade and support normally forming a light-tight connection when the shutter blade is in a position of rest, said supporting plate embossing completely encircling the exposure opening, said embossings including walls curved in cross-section so that e the trigger, by tensioning and releasing said spring, may swing the blade, separating the embossings for making an exposure.

'2. in a photographic shutter, the combination of a plane supporting plate including an exposure aperture, plane shutter blade pivotally attached to the supporting plate and movable on the stud to cover and uncover the exposure aperture, a trigger, spring means operable by the trigger ior actuating the shutter blade to make an exposure, and interiiitting embossings bent from the plane of the supporting plate and shutter blade, the former surrounding the exposure aperture adapted to form a light-tight connection and a rebound check,

6. In a photographic shutter, the combination of a plane supporting plate including an em posure aperture, a plane shutter blade pivotally attached to the supporting plate movable on the stud to cover and uncover the expos'ine oper ture, a trigger, spring means operable by the trigger for actuating the shutter blade to make an exposure, an annular forming about the ex posure aperture bent irom the plane of the supporting plate, pair of annular iormings equally spaced from the shutter blade pivot and each adapted to engage the annular supporting plate forming, each shutter plate forming being bent from the plane of the shutter blade, the form-=- ings including walls angularly disposed in crosssection adapted to form an interfitting connection between the supporting plate and shutter blade when the latter is in a normal position of rest.

9. In a shutter for cameras, the combination with a supporting plate having an aperture therein, of a shutter blade pivotally mounted thereon, mechanism for moving the shutter blade on the supporting plate for making an exposure through the exposure opening, said shutter and supporting plates both comprising flat plates lying substantially in a plane, embossings on the shutter blade and supporting plate formed to one side of each of the flat plates, said formings being substantially complemental in shape, said pivotal support for said shutter plate including a loose fit with the shutter blade whereby said shutter plate may move at an angle to the plane of the flat material for making an exposure so that the complemental formings will interilt and prevent light from entering around the exposure opening.

' MILLER R. HUTOHISON, J2.

on de- 

